Knitting machine



" March 7 1967 v v F.SEILER I 3,307,376

KNlTTING MACHINE Filed June 4-, 1963 3 Sheets$heet 1 INVENTOR. fk/rzSEILCTQ March 7, 1967 Y F. SEILER 3,307,376

KNITTING MACHINE 7 Filed June 4, 1963 s Sheets-Sheet :1

INVENTOR. F1 T2 S'lLE/Q United States Patent 4 Claims. (01. 66-70) Theinvention relates to fiat knitting machines having needle beds forming aV, in which in known manner a multiplicity of straight paralleltransverse grooves for accommodating and guiding latch needles aremilled, these needles being so shaped and disposed as to permit normalknitting as well as the transfer of loops immediately from one needle tothe other in the same stroke of the carriage.

The transfer of stitches on a knitting machine, that is to say thetaking up of stitch loops from the needles of one needle bed on to theopposite bed or the same bed, permits a very considerable expansion ofthe pattern range of the machines provided for this purpose. In this wayit becomes possible on the one hand to knit interesting openworkpatterns or to effect automatic transfer from 1/ 1 articles to 2/2articles, while on the other hand reductions in width can be made forthe purpose of producing shaped knitted parts.

Processes and devices for transferring stitches are already known inlarge number and in the most widely varying forms of performance andfinish. One group of these makes use of special auxiliary members whichcooperate with the ordinary knitting needles, while in another group theneedles themselves are so constructed that they can operate the stitchtransfer process by themselves alone. For comparison with the knittingmachine in accordance with the invention, in what follows only thesecond group will be cited, as this machine works with specially shapedneedles without the cooperation of additional transfer implements.

A further feature marking a difference between the known stitch transfermethods, is the additional fact that in one of them one of the twoneedle beds has to be displaced by half a needle gauge, while the otherproceeds without this auxiliary measure. In this respect again in whatfollows only the second category will be taken into account, as nooffsetting or displacement is necessary for the stitch transfer whichwill be described below.

The appropriate specially formed transfer needles can be divided againinto two main groups; those with stitch spreading members (springs,wires, loops, etc.,) arranged laterally to the needle stem and thosewith recesses provided unilaterally in the stem. In the first group thestitch loop to be transferred is spread out by the spreadin-g member sothat the transfer needle can pass through it (between the stem of theneedle and the spreading member), while in the second the head of thereceiving needle is applied against the transfer needle and so is ableto slide as the latter rises in its lateral recess and simultaneouslythere-by into the stitch loop stretched obliquely above. This secondsystem is taken as a basis for the transfer process in the knittingmachine in accordance with the invention. I

All the above mentioned methods and devices from their first becomingknown to the most recent times, have always been applied in knittingmachines in such a way that in one and the same row of stitches it hasonly been possible to carry out the transfer but not at the same timethe forming of the stitches. The result of this that for producing acomplete knitted row consisting of ordinary and suspended stitches atleast two passes of the carriage are necessary only one of which cancarry out the desired 3,307,376 Patented Mar. 7, 1967 operation. This ofcourse means a noticeable reduction in the productivity of the machine.

Now, in evaluating a modern knitting machine, in addition to the patternpossibilities and the quality of the goods produced, the capacity of themachine is also critical and recently a number of proposals have beenmade for equipping the machines with devices which permit knitting andtransferring in the same stroke of the carriage.

One proposal envisages providing the known transfer needles with lateralspreading springs, by which the loops to be transferred are opened andsimultaneously brought into a favourably inclined position for insertingthe opposite transfer needle. In this connection the said transferneedles are arranged symmetrically to the axis of symmetry of thearticle to be knitted, and also to the transverse centre line of theneedle bed, that is to say one half of the needle bed contains needleswith right hand spreader springs and the other with left hand spreadersprings. In this connection in order to obtain satisfactory l/ 1 ribbedgoods or fabrics the needles must be accurately placed in relation tothe gaps in the opposed needles, and the needle grooves are thereforemilled in, in the usual manner uniformly spaced over the whole bedlength. The loops are suspended in this case without the usual 1/2 gaugeracking on the one needle bed in relation to the other, which makeslaterally widely projecting spreader springs necessary, which in turnleads to wide needle grooves and consequently to undesirably weak needlebed webs. The result of this is an excessive stretching of the openloops, which, depending on the yarn material used, can easily lead tothe threads tearing. For the same reasons it is also impossible to knitnarrow-mesh articles With out difficulty. Furthermore, in the centralzone of one of each of the two needle beds, because of the abovementioned symmetrical needle arrangement, there is in each case anunoccupied needle groove, the needle opposite which cannot thereforefind any stitch to transfer. The result of this is a certain restrictionof the freedom of patterning in this zone.

One solution has already been disclosed, which does indeed likewiseprovide a symmetrical distribution of the spreader spring needles,mirrorimaged in relation to the center of the needle bed, incorrespondingly wide grooves, in which however a special narrow grooveis milled accurately in the center of the needle bed, which accommodatesan ordinary knitting needle. The opposing needle beds are accuratelyplaced in this connection in relation to gaps, and their transferprocess is facilitated by predominantly lateral bending of the transferneedles, thus making it possible to have comparatively narrow spreadersprings.

In another known form of embodiment the normal needle beds are againfitted with spreader spring transfer needles, but in a completelyuniform distribution over the whole bed length, that is to say withoutsymmetry in relation to their center line. To avoid excessive wideningof the suspension loops the lateral projection of the spreader spring ishere restricted to the unavoidable minimum, so that while on the onehand admittedly narrow needle grooves and hence strong needle bed websare obtained, on the other hand however, it becomes necessary to offsetthe bed of the transfer needles in known manner by about half the gaugeof the needles, in order to ensure insertion in the only slightly openedloops. This racking results in a one-sided distrubance of the normalcrossing so that it may happen that the ribbed article continuouslyknitted with the taken-up pattern will likewise be distortedone-sidedly.

As a third solution necessitates, in the narrowing process in additionto the ordinary knitting needles, special points for the stitch transferprocess, that is to say is based on a quite different basic principlefrom that of the present invention then there is no need here indescribing generally the position of known art to give a more detailedcomparison of the two solutions.

The object of the invention is to avoid the disadvantages of thehitherto known constructions. -It relates to a knitting machine, inparticular a flat knitting machine, with two opposed needle bedsinclined in relation to one another in the shape of a V, in which inknown manner a multiplicity of straight parallel transverse grooves forreceiving and guiding latch needles are milled, in which connectionhowever, differently from the usual uniform pitch over the whole bedlength, one groove lies accurately in the centre of the needle bed andthe two directly adjacent grooves to right and left are at a distance ofonly half the needle gauge, while all the other grooves on either sideadjacent outwardly have the full normal gauge so that the grooves in onebed located opposite the spaces between the grooves of the other bed.

In a known manner (see US. Patent No. 3,102,404) the middle groove isfitted with an ordinary straight knitting needle while in all the othergrooves special knittingtransfer needles bent laterally by half theneedle gauge are inserted in such a way that the lateral bending of thefront needle stem extends right and left of the straight central needlecontinuously from its path, thus producing a completely mirror-likearrangement of the needles in relation to the bed centre, withabsolutely uniform spacing of the needle hooks with correct normalcrossing. The lower straight front part before the bend, containing thehook and latch of the needle stem, serves in this connection for theusual loop-forming process, while the upper, also straight central pathof the needle body has beyond the bend the known lateral recess for theinsertion of the transfer needle during the loop take-up. The hooks onthe front straight needle stems in one needle bed are located in thisconnection, because of the said lateral bending, accurately opposite theupper straight needle bodies in the other needle bed, so that for thestitch transfer process known per se no 1/2 racking is necessary. It isthus possible to produce in the same stroke of the carriage bothcompletely uniform rib knitting and also transfer patter and/ ornarrowings or reductions in the width.

The knitting machine needles with lateral bending of the needle stem arealready known per se but this bending has the duty of bringing the loopto be transferred into such a lateral oblique position that the oppositetakeoff needle can easily pass through it. In other words the top-arm ofthe bend has here an essential function within the framework of thetransfer process, while as will appear more clearly in the followingdescription, it represents in the subject matter of the invention onlythe natural connecting member of the two straight needle stern partsdisplaced laterally in relation to one another.

A specific embodiment of the invention will now be described by way ofexample with reference to the accompanying drawings in which:

FIGURE 1 is a section through two needle beds mounted on the machineframe, along the line II of FIGURE 2.

FIGURE 2 is a plan view rotated into the plane of the drawing of the twoneedle beds along the lines IIII of FIGURE 1.

FIGURE 3 is a side elevation of the front half of a knitting transferneedle.

FIGURE 3A is a cross-section of FIGURE 3 taken along line 3a3a thereof.

FIGURE 3B is a cross-section of FIGURE 3 taken along line 3b3b thereof.

FIGURE 4 is a plan view of the same needle.

FIGURE 5 is a part cross-section through the two needle beds with twoneedles in the uppermost knitting position.

FIGURE 6 is a similar section with the right hand needle in the highestejection position for casting off the stitch and the left hand needle inthe insertion position for the stitch transfer.

FIGURE 7 shows the hook of a take-over needle approaching the groove ina delivery needle, at the beginning of the stitch transfer.

FIGURE 8 shows the hook partly located in the groove.

FIGURE 9 shows the hook partly inserted in the loop.

FIGURE 10 shows the hook nearly completely inserted in the loop.

FIGURE 11 shows the hook as it begins to descend, and

FIGURE 12 shows the loop in the hook.

In FIGURE 1 the two needle beds 1 and 2 of a V-bed flat knitting machineform an included angle between them of about This reciprocal position ismaintained by a suitably constructed needle bed carrier, principallyconsisting of two angle cross-members 3, and 4, and end face walls 5 and6 at the two machine ends. In the needle beds 1 and 2 are milled inknown manner a multiplicity of straight, parallel needle grooves 7 and8, the depth of which in different cases can vary over their length asshown in 7, 7", 8', 8", according to the space requirements of theknitting and needle entrainment de vices accommodated therein. In thisconnection in the upper needle bed half, which contains the actualneedles, the groove base is completely rectilinear and parallel to theneedle bed surface. By contrast with the ordinary groove arrangementwith a uniform distribution over the whole bed width, here in bothneedle beds, right and left of a center groove 9, 10 which is locatedexactly in the bed center there is milled in each case a groove 11, 12and 13, 14 (FIGURE 2) at a distance of only 12 of the needle gauge orpitch, while the other grooves 15, 16 adjacent on both sides to the bedends, again have the normal regular l/ 1 needle gauge or pitch betweenthem. These grooves 15, 16 are in this connection arranged in the twoopposite needle beds in such a way that they are accurately related togaps in respect of one another, as is also the case with ordinaryknitting machines. Between all these grooves milled-in in this wayparallel fillets or webs 17, 18 are left which are very strong with theexception of the two webs 19, 20 enclosing the central grooves 9, 10,the thickness of which is smaller because of the above mentioned 1/2gauge in this bed central zone. Not all the webs extend over the wholeneedle bed width, but end at a certain distance below the knocking overcomb at the edge A. Here furthermore they are undermilled, in such a waythat a rectangular incision E is produced at their root, which permitsthe partial introduction of the oblique bent arm of the knittingtransfer needle described further below. The comb webs 21 are separatelyinserted in known manner and are fixed by screwed-on clamping bars 21a,so that if required they can easily be changed. As in the case of thesaid milledin grooves 15, 16 these comb webs are located in the opposedneedle beds exactly in relation to the gaps and in 1/1 gauge with theexception of the two webs 21' to the right and left of the centralstraight knitting needles which have a narrower spacing.

In the above described grooves the various knitting implements areinserted in the usual manner, of which here only the actual needles willbe considered, and not any possible associated push rods or platens. Asalready mentioned the central groove exactly in the center of the bed isoccupied by an ordinary straight knitting needle 22 of the usual latchneedle type which need not therefore be described here in more detail.All the other grooves contain special laterally bent knitting take-upneedles, of which two kinds are present, one kind 23 with a left handbending viewed from the hook and another kind 24 with a right handbending of the front needle stem. FIGURES 3 and 4 show the needle type23 on a larger scale, only the front half which affects the matter herebeing shown. These novel needles consisting of one piece containessentially two basic elements,

namely an ordinary latch knitting needle portion T and a stitch transferneedle portion R known per se one of each of which works in alongitudinal plane of its own, offset laterally in relation to oneanother, in which connection these two elements are however connected byan oblique connecting member B to form a rigid whole. In this way thereis obtained the bent shape of the complete member which has already beenmentioned several times. Its front portion T has the usual hook 23a andthe usual latch 23b which can swing round the pivot 23c and is guided inthe slot 23d of the needle stem. In the central portion R are locatedtwo recesses one of which 23c (FIGURE 3a) takes the form of a grooveopen towards the underside of the needle and provided in the sectionplane, a-a with lateral facets 23 while the most important recess 23g(FIGURE 3b) is completely open both laterally and also underneath over agiven length in relation to the needle stem, in this high zone.Fundamentally such a construction of the needle stem has already beendisclosed by German Patent 692,981, the form of embodiment selected inconnection with the subject matter of the invention represents however,a simplified variant of the original patent. Instead of the transitionfrom the low front part of the needle to the high central part there isfound the angular indent 23h likewise known in connection with transferneedles. All these needles 22, 23, 24 are guided and prevented fromfalling out by cover bars 25 and 26 in the two needle beds 1 and 2respectively on the bottom of the grooves 7 and 8 respectively.

A knitting machine fitted with the above described needle beds andneedles Works as follows: different reciprocating movements in thelongitudinal direction of the grooves are imparted in the conventionalmanner to the needles by the reciprocating motion of a carriage (notshown) over the needle beds by means of suitably arranged cams which acton the need-1e or push-rod feet. Each to or fro movement of the carriageconstitutes a stroke. The normal original position (comb level) is shownin FIGURE 1, FIGURE 5 then shows the uppermost needle position duringthe normal knit-ting (loopforming) process. It can be seen from thisthat here in the two needle beds only the straight front part T of theneedle stem is involved, while the oblique bending and the high centralpart R remain inoperative inside the needle bed. In this connection theneedle crossing is effected over the whole length of the bed in acompletely regular reciprocal needle spacing producing equal armed loopfillets.

FIGURE 6 which relates to the stitch transfer from the needle bed 2 tothe needle bed 1 is generally directed to explaining the basically knownstitch transfer process. The delivery needle 23 is accordingly shown inits extreme ejection position in which the central part R of the needlestem has been brought into the working zone of the opposite take-overneedle 22, in such a way that it projects by about of its length beyondthe knocking over comb. Because of the lateral displacement of thiscentral part R in relation to the front part T the hook of the needle 22is located accurately in relation to the centre of the stem part R ofthe needle 23, so that the said hook can travel safely into the lowerand laterally open recess 23g without a preparatory needle bed rackingbeing necessary. The most important phases of the stitch transferprocess are then illustrated on a larger scale by FIGURES 7 to 12. Thisprocess corresponds in principle to that already described in GermanPatent 692,981, but with some simplifications. FIGURE 7 shows theinstant in which the hook of the take-over needle enters the widening 23of the groove 23c on the underside of the delivery needle 23 in order toact as an additional stripper member of the loop M hanging on these twoneedles, that is to say to move the latter during the further rise ofthe needle 23 in support of the tensile stress produced by thedrawing-off of the article towards the angular indent 23h. In FIGURE 8can be seen the definite end position of this displacement process, inwhich the hook of the needle 22 has already penetrated to a certainextent in the groove 23:: and the loop M begins to assume an obliqueposition in relation to the stem of the needle 23. With a further riseof the needle 23 the loop M then lies as can be seen in FIGURE 9,completely in the indent 23h, so that the former because of the draw-offtension moves more and more into an expressly oblique position, in whichconnection it is simultaneously somewhat extended. Meanwhile the need-1e22 likewise continues its rise so,that its hook begins to be inserted inthe obliquely lying extended loop M. The closing stage of this actualinsertion process can then be seen from FIGURE 10, in which the deliveryneedle 23 has reached the highest point of its rise while the hook ofthe takeover needle 22 is closely applied, with a slight lateraldeviation, against the perpendicular base surface of the lateral recess23g. While the delivery needle 23 now stays for a while in its highestejection position, the hook of the needle 22 completes the insertion inthe loop M, projecting with safety a little beyond this. Next the needle23 begins its return descent, during which as shown in FIGURE 11 thehook of the needle 22 which has completely penetrated into the lateralaperture 22g is forced out of this aperture with a predominantlysomewhat stronger bending over, so that it is applied against thecorresponding outer side of the stem of the needle 23. In thisconnection the loop M is now held back by the needle 22, by which it isagain straightened out and released from stress, With a further descent,correctly synchronised in relation to one another in time, of the twoneedles 22 and 23, the taken-over loop M finally slides in turn, as isshown in FIGURE 12 in a desired intermediate stage, into the hook of theneedle 22 and on the other hand over the whole length of the finelypolished front stem of the needle 23, in which connection this loopbecause of the bent shape of the said stem is deflected laterally, andin sliding forward and over the latch 23b closes the latter and thenleaves the needle in the usual manner. Thus the complete stitch processis ended.

It can clearly be seen from the preceding description that on a flatknitting machine equipped with needle beds in accordance with theinvention and bent-over knitting transfer needles, both correctly ribbedarticles and also transferred patterns and/or narrowings can be madesymmetrically in one and the same carriage stroke without any needle bedracking being necessary. A satisfactory quality of the articles producedis obtained together with a higher rate of production.

Iclaim:

1. In a stitch-transfer V-bed flat knitting machine having two opposedinclined needle beds: a straight transverse centra-l groove in thecenter of each needle bed, the central groove of one bed being laterallyoffset from that of the other; a first transverse groove on each side ofthe central groove of each bed, parallel thereto and spaced therefrom byone-half the needle gauge; and a.

like number of a plurality of transverse grooves lying on either side ofeach central groove and beginning at one full needle gauge from a saidfirst groove, said plurality of grooves extending parallel to thecorresponding central groove and adjacent grooves of said pluralitybeing separated by one :full needle gauge, said central grooves, firstgrooves, and plurality of grooves all having a common width forreceiving each a single knitting need-1e.

2. A knitting machine according to claim 1, including a straightknitting needle located in each central groove of each bed; and locatedin each of said first grooves of each bed and each of said plurality ofgrooves of each bed a knitting-transfer needle having first and secondstraight and parallel portions laterally olfset by one-half of a needlegauge and a bent portion intermediate the ends of the needle forconnecting together said first and second portions.

3. A knitting machine according to claim 2, wherein said bent portionsof the knitting-transfer needles located on one side of a central grooveare all bent in the same direction in the plane of the bed and thosebent portions of the knitting-transfer needles located on the other sideof the same central groove are all bent in the opposite direction in theplane of the bed. 1

4. A knitting machine according to claim 2,- wherein said first portionof a knitting-transfer needle contains a latch and terminates in a hook:and serves in the loop forming process; and said second portioncontains a lateral recess for insertion therein of a receiving needleduring a loop transfer.

References Cited by the Examiner UNITED STATES PATENTS 410,858 9/1889Scott 6673 XR 2,521,786 9/1950 Granov 66-70 3,1 15,760 12/1963 Pierce661 15 XR FOREIGN PATENTS 4,232 1884 Great Britain. 27,730 1903 GreatBritain.

MERVIN STEIN, Primary Examiner.

W. C. REYNOLDS, Assistdnt Examiner.

1. IN A STITCH-TRANSFER V-BED FLAT KNITTING MACHINE HAVING TWO OPPOSEDINCLINED NEEDLE BEDS: A STRAIGHT TRANSVERSE CENTRAL GROOVE IN THE CENTEROF EACH NEEDLE BED, THE CENTRAL GROOVE OF ONE BED BEING LATERALLY OFFSETFROM THAT OF THE OTHER; A FIRST TRANSVERSE GROOVE ON EACH SIDE OF THECENTRAL GROOVE OF EACH BED, PARALLEL THERETO AND SPACED THEREFROM BYONE-HALF THE NEEDLE GAUGE; AND A LIKE NUMBER OF A PLURALITY OFTRANSVERSE GROOVES LYING ON EITHER SIDE OF EACH CENTRAL GROOVE ANDBEGINNING AT